1. Field of the Invention
The present invention concerns a device for operating locks by pushing or pulling an operating member such as a handle accessible to a user.
2. Description of the Prior Art
These operating devices enable a door to be opened by application of a lever arm movement either by pushing the operating member towards the door or by pulling it in the opposite direction.
The present invention relates more particularly to an operating device of this type which can be added to any lock, for example a mortice lock, including a rod, usually of square cross-section, which is rotated to actuate a bolt mounted in the lock.
This square cross-section rod operates the bolt through a nut rotatably mounted in the lock case. The nut actuates the bolt and includes a square hole in which the square cross-section rod is inserted.
These devices are intended in particular to replace the existing operating members, e.g. handles, of locks already inset into the edge of a door and of the kind requiring the user to rotate the member and at the same time to push or pull it to open the door. These operating members are less ergonomically efficient than the push-pull operating devices intended to replace them.
However, in the case of locks to be inset into the edge of a door, for example, a predefined direction of rotation of the square cross-section rod corresponds to a downward tilting movement of the handle operating the rod.
Accordingly, the direction of rotation of the square rod is reversed depending on whether the lock is lefthanded or righthanded on the same side of the door.
To avoid unnecessary multiplication of the number of operating devices required, the devices must be able to operate the locks to which they are fitted independently of the direction of rotation of the square rod, at least for each of the push and pull types.
It is preferable for these devices to be able to operate the locks to which they are fitted independently of the direction of rotation of the square rod and of the mode of operation: push or pull.
In the locks previously mentioned a spring returns the nut to its rest position after it has been actuated by the user by means of the operating member mounted on the square rod.
This spring holds the nut in a rest position such that a conventional handle mounted on the square rod to serve as an operating member is held in a substantially horizontal plane.
To prevent the handle drooping under the horizontal plane the spring when fitted is adapted to coordinate the orientation of the nut with that of the handle so that the latter is oriented in a direction above the horizontal plane at an angle usually between 0.degree. and 7.degree..
The push or pull devices to be fitted to these locks and adapted to operate these nuts must therefore also provide adequate compensation to allow for this variable "pre-orientation".
The present invention has the following mutually independent objects.
One object of the present invention is to provide an ergonomically efficient push or pull type lock operating device.
Another object of the present invention is to provide a push or pull type lock operating device which is able to operate a lock independently of the direction of rotation of the square rod and therefore of the nut of the lock.
A further object of the present invention is to provide a lock operating device able to operate a lock independently of the direction of rotation of the nut of the lock and of the mode of operation: push or pull.
A still further object of the present invention is to provide a lock operating device able to operate a lock independently of previous angular positioning of the square cross-section orifice in a lock nut.
The objects of the present invention as stated above may also be achieved in combination.